Camera focusing device.



H T. OLIVER.

CAMERA FOGUSING DEVICE.

APPLICATION FILED APR. 18, 1912.

1,076,694. Patented 001;. 28,. 1913.

focus UNITED STATES PATENT ()FFRJE.

KERRY T. OLIVER, 0F NEWARK, NEW JERSEY, AS SIGNOR, BY MESNE ASSIGNMENTS,TO NEW JERSEY PATENT COMPANY, OF WEST ORANGE, NEW JERSEY, A. CORPORA-TION 0F NEXV JERSEY.

CAMERA IE OCUSING DEVICE.-

Specification of Letters Patent.

Patented Oct. 28, 1913.

To aZZ wizom it mag concern Be it known that I, H NRY T. ,Omvnn, acitizen ofthe United States, residing at Newark, in the county of Essex,State of New Jersey, have invented certain new and useful Improvementsin Camera Focusing Devices; and I do declare the following to be a full,true, and exact description of the said invention, such as will enableothersskilled in the art to which it appertains to make use of the same.

This invention relates to a device for focusing a lens in a camera orother similar instrument. In -certain types of cameras, the lenses aremounted to be moved toward and away from. the sensitized plate and thecamera is provided with fixed marks, each mark indicating a position atwhich the lens must he set to focus an object at a dis tance' from thecamera indicated by that mark. The operator estimates the distance ofthe object from the camera and then sets the lens in a position tocorrespond to that,

distance indicated by ma ks on the instrument. My device is 01 thisclass, but I have provided an exceedingly simple and yet exceedinglyaccurate device of this type which is especially useful in very shortsuch as used in motion in .ras, in which only a very slight of the lenstoward. or away from the i l plane is required forconsidcrahlovariations in the distance of the object from the camera.

Vv ith these and other objects in view, the invention consists ofcertain novel features of construction and arrangci'ncnt of parts whichwill be more fully described and pointed out in the appended claims.

In the drawings Figure 1 is a side elevation of the lens mount attachedto a portion of a motion picture camera. Fig. 2 is a front elevationthereof. Fig. 3 tudinal section of the mount showing a fragmentaryportion of the mechanism of a motion picture camera to which the mount,as illustrated, is attached. Fig. 4 is a front view of the mount withthe lens and its barrel removed, to show the arrangement of the splitnut device.

The corresponding parts are referred to both in the drawin s andfollowing descrip tion by similar rc ercnce characters.

In the drawings 10 represents the usual picture is a longilens in itsholders. This lens may be of any type, but as shown is of the ordinarycombination type with a diaphragm between the lens. This diaphragm islocated at 1 1 and has attached thereto a tubular member 12 which, whenrotated, closes or opens the diaphragm in the usual manner. The lens 10,1s mountfd in a ring 13 attached to a barrel 1 1, WllCll has fastened toit at 15 a sleeve for a purpose to be hereafter pointed out. The barrel14 is threaded externally as shown in Fig. 3, and fits in a tube 16which is fastened to the front of the camera by screws 17 in theordinary manner. The tube 16 is internally threaded and has fitting init a circular nut 18, and a jam nut 19. The circular nut 18 has aconical bore. into which is threaded a tapered circular split nut 20having pins 21 engaging with openings in a rib in tube 1'3 to preventthe rotation of the nut 20. The nut 20 is internally threaded and sofaras the adjustment of .the lens is concerned, is practically apart ofthe tube 16, as-is the circular/nut 18, and

I have used the expression tubular mem-- ber in the appended claims toindicate gcnerally the tube 16 with the internal threads integral withit, or as attached to it, as shown in the drawings. The threads on thebarrel 14 engage "with the threads on the nuts 18 and 20, so that, whenthe barrel 1&- (a5 is rotated, the barrel, with the holder 13111111 thelens 10, is moved toward or awayirom the focal plane of the. sensitized.surface. I iltU/('lllUSiltlllECl at 22 a portion of the aperture plateof the ordinary motionpicture camera behind which is held the film atthe time the photographs are being taken, and.

23 represents the ordinary rotary shutter of such a camera.

V In the side of the tube 16 I have cutan 9.5 opening- 94 and directlyabove this opening have mounted a member 25 having thereon an index mark26. On that portion of the barrel 1 1 which passes across this openingwhen the barrel is screwed in or out of the 109 tube 16, I have placed aseries of index marks or lines extending entirely around the barrel, sothat when one of these marks is brought opposite the index mark 26, itwill be shown that the lens is located in a 105. predetermined position.I have also placed at the edge of the peripher of the tube 16 a seccindindek mark 2 7, 23.11 have placed on 11, the cylinder 12 is rotatablymounted in a bore of the barrel 14, so that when the barrel 14 isrotated, the cylinder 12 is carried with it, and therefore the openingof the diaphragm 11 is not disturbed. The cylinder 12, however, fitsrather loosely in the barrel 14, so that the rotation of the cylinder 12does not affect the position of the barrel 14. As shown, the cylinder 12projects beyond the barrel 14 so that it may be grasped by the hand ofthe operator. While I have found this arrangement for controlling thediaphragm the/ most convenient, I do not wish to confine myself to theparticular arrangement shown. All that is required is a handlecontrolled by'the operator, turning with the barrel 14 when the latteris turned, but free to turn in the barrel 14, when adjusting thediaphragm.

The split nut 20 and the adjusting nut 18 are provided to take up anywear in the threads of the barrel 14, so that the barrel is always heldrelatively tightly in the tube 16. By turning the nut 18 it will be seenthat the sections of the split nut 20 will be moved radially by reasonof the tapered engaging surfaces between 18 and 20, thus tightening thesections on the threads of the barrel 14. This adjustment is arefinement which, of course, is not necessary to the successfuloperation of my lens-mount, and the tube 16 might have internal threadsdirectly upon it to engage. with the external threads of barrel 14.

The position of the two sets of index marks is determined by setting upthe lens and focusing itvery accurately on objects at differentdistances from the camera. For instance, an object is placed just 25feet from the camera, and the lens accurately focused thereon by turningthe barrel 14 until the image is sharp at the focal plane. A mark orline is then made on the side of the barrel 14 opposite the index mark26 and extending entirely around the barrel and another mark made on thesleeve 15 opposite the index mark 27. The index marks for otherdistances are correspondingly. located, and it is obvious that all thatis required thereafter to focus on an object, say 25 feet from thecamera, is to turn the barrel 14 until the index marks for that distanceare opposite the index marks 26 and 27. i

The index on the side of the barrel 14 serves to indicate roughly thedesired setting of the lens, and the index on the sleeve 15, the exactsetting. The screw threads on the barreL 14 are very fine, so that acomsleeve 15 will make several revolutions and i there would beconfusion as'to the position of the lens when a given mark is oppositethe index 27, were it not for the index on the side of the barrel 14.This index indicates directly the position of the lens but only roughly,since any failure to aline a mark thereof with the mark 26 results in anerror of like amount in setting the lens. By the use of both indices, asetting may be had which will be very exact and without confusion. Clihebarrel 14 is first turned until the desirtd distance is indicated at 26and then adjusted until the same distance is-indicated by the mark 27,this last adjustment compensating for any error in the first set-- ting.

For some purposes, the one index device on the side of the barrel 14will suflice, and indeed, with a coarse threaded barrel 14 and a narrowlimit of longitudinal adjustmentof the lens 10, the index device on thesleeve 15 will be sufficient. I prefer, however, to

use them in combination, the index on the side of the barrel 14 to givea rough and ready adjustment, and the index on the sleeve 15 to give anexact or practically micrometer adjustment.

\Vhile I have located my two systems of indices in the most convenientpositions, it is obvious that they need by no means be limited to thepositions illustrated. All that is essential is that one of them shallmark off directly the longitudinal position of the barrel 14 and theother, the amount of rotation of the barrel 14.

While I have illustrated and described a threaded arrangement foradjusting the relative positions of the lens and the focal plane, I donot wish to be limited to such arrangement.

Many features of my device may he used with any other adjusting device,such, for instance, as the well known rack and pinion, or even withoutany such device, as when the lens holder is held frictionally in thetube fastened to the camera.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is as follows:

1. In a camera focusing device, an inter anally threadedtubular memberadaptedto be attached tot-the camera, an externally threaded barrel-insaid tubular member havingthe. threads thereof engaging with the threadsof said tubular member, a lens in said barrel, and an index device topermit the location of said barrel longitudinally in said tubular memberat predetermined positions, substantially as described.

2. in a camera i'wusing device, an internally threaded tubular memberadapted to be attached to the camera, an externally threaded barrel insaid tubular member having the threads thereof engaging With the threadsof said tubular member, a lens in said barrel, and a diaphragmcontrolling device carried by said barrel, substantially as described.

3. ln earners. focusing device, a tubular member adapted to be attachedto the camera, a barrel movably mounted Within said tubular member, alens in said barrel, means operated by the rotation of said barrel toadjust the longitudinal relation of said tu bular member and barrel, andan index device on the peri 'ihery of said barrel to loate it inpredetermined positions in its rotat on within said member,substantially as described.

ll. In. a camera focusing device, a tubular member adapted to beattached to the camera, said tubular member having an opening in itsside and an index mark adjacent to said opening, and a. barrel, movablelongitudinally .lin said member, said barrel l'nwing eries of indexmarks adapted to co perate with the o 'n ning and index mark on saidtubular member to permit the location or id barrel in predeterminedlongitudinal relation to said member, substantially as described.

5. In a camera focusing device, a tubular member adapted to be attachedto the camera, said member being provided with internal screw threads,and having an opening in its side and an index mark adjacent to saidopening and having a second index mark on the periphery thereof, anextennallv threaded barrel Within said member having its tl'lIOiIdSengaging with the threads of said member, said barrel having a series ofindex marks adapted to coilperato with the opening and index mark on thesaid member to permit the location of the said barrel rzmghly inpredetermined longitudiual relation to said member, and having. a blondseries or" index marks on the periphery thereof adapted to cooperatewith the second index mark on said member to permit the location of saidbarrel in exact predetermined longitudinal relation to said member,substantially as described.

6. in a camera focusing device, a tubular member adapted to be attachedto the camera. a barrel movably mounted in said memher and adju tablelongitudinally thereof by the rotation of said barrel, a lens in saidbarrel, an adjustable diaphragm for said lens and means for adjusting;said diaphragm, comprising a hollow cylinder rotatably mounted in saidbarrel, substantially as described.

7. In a camera focusing device, a tubular member adapted to be attachedto the came a, a barrel movably mounted in said memher and adjustablelongitudinally thereof by the rotation of said barrel, a lens in saidbarrel, an adjustable dia 'al'iragn'i for said lens and means foradjusting said diaphragm, comprising a hollow cylinder rotatably mountedin said barrel and projecting beyond the end thereof, substantial y asdescribed.

8. In a camera focusing device, a tubular member adapted to be attachedto the caroera, a barrel movably mounted in said member and adjustablelongitudinally thereof by the rotation of said barrel, a lens in saidbarrel, an adjustable diaphragm for said lens and adjusting means forsaid dia phragm, mounted in said barrel and normally turning therewithand rotatablv adjustable in relation thereto, substantially asdescribed.

9. In a camera focusing device, a tubular member adapted to be attachedto the camera, a barrel longitudinally movable within said member, andan. index device to permit the location of said barrel longitudinally insaid tubular member at undetermined posi tions, substantially asdescribed.

10. In a camera focusing device. a tubular member adapted to be attachedto the camera, said member having an opening in its side and an indexmark adjacent to said opening, a barrel longitmlinally movable withinsaid member, and a lens in said barrel, said barrel having index marksthereon adapted to'cooperate with the opening and index mark on saidtubular member to permit the location of said barrel and said member atpredetermined positions, suit-stalk tially as described.

11. In a camera focusing device, an. internally threaded tube adapted tobe attached to the camera, an internally and externally threadedadjusting nut in said tube and engaging the threads thereof, saidadjusting not having a conical bore, an internally threaded split rinthaving a conical surface on its exterior, said conical surface engagingthe conical bore of the adjusting not, conneetions between said splitnot and said tube to prevent relative rotation thereof, an rxlernallythreaded barrel, with its threads en-- gaging the internal threads ofthe said split nut and the said adjusting nut and a lens in said barrel,substantially as described.

12. In a camera focusing device. a tube adapted to be attached to thecamefia, a barrel within said tube, a lens in said barrel, screw threadconnec ons between said tube and said barrel and means to tighten the 1s lit nut to clamp the threads thereof on the contact between thethreads of said connecthreads of the said barrel, substantially astions, substantially as described. described.

13. In a camera focusing device, a tube This specification signed andwitnessed 5 adapted ti) be attached to the camera, an in this 16th dayof April 1912.

ternally tn'ended s lit nut attached to an inside of the said tiibe, abarrel inside said HENRY OLIVER tube and split nut and having externalWitnesses: threads engaging with the internal threads Gnome F. SEULL, 10of the split nut and means to close in the W. LAWSON DYER.

